Arthroscopy surgery is a minimally-invasive surgery that involves the repair of tissue inside or around a joint. In shoulder arthroscopy, for example, common injuries include a torn or damaged cartilage ring or ligaments (causing shoulder instability), a torn rotator cuff, or a torn or damaged biceps tendon. Each of these injuries necessitates the reattachment of soft tissue (that is, the ligaments or tendons) to bone. Current methods of arthroscopic fixation of soft tissues to bone involve the placement of suture anchors in bone, and reducing tissue to bone by passing a suture through the tissue and tying surgical knots to secure the tissue against the bone.
In the construction of suture anchors, it is often desirable for the anchor to be made of different materials. For example, a harder (typically metal) tip, is useful for driving the anchor into bone, while a softer (typically polymer) main body can be reabsorbed into the body over time. However, constructing a suture anchor from different materials presents difficulties in connecting the tip to the body. Current methods for connecting a metal tip with a polymer main body are by over-molding of the parts, or the use of a stay suture. However, both of these methods add costs to manufacturing the suture anchor and may lead to unreliability in the surgical procedure.